$-\dfrac{5}{2} - \dfrac{6}{10} = {?}$
Solution: $ = - {\dfrac{5 \times 5}{2 \times 5}} - {\dfrac{6 \times 1}{10 \times 1}} $ $ = - {\dfrac{25}{10}} - {\dfrac{6}{10}} $ $ = - \dfrac{{25} - {6}}{10} $ $ = -\dfrac{31}{10}$